F6 Amplifier

I read what mr Pass wrote about adjusting for max or min second HN harmonic.
How have you adjusted your amps?
Hi Ryssen. Does your diyF6 effectively damp the woofer of your loudspeaker? lhquam has practiced the guidelines of Mr. Pass shown above, and fully detailed the performance of his Teaser diyF6. Still, he concluded that his loudspeakers are not the best mates for it. Adjusting the harmonic balance worked for some DIYers, like generg, buzzforb, etc. but not for him.
 
Mr. Srajan Ebaen used the loudspeaker Aries Cerat Gladius to evaluate F6 which he liked. He had also reviewed this loudspeaker earlier using F5 and liked this amp very much. Fortunately, the impedance versus frequency curve of the Aries loudspeaker was published by its maker. Way different from that of lhquam's loudspeaker for comparison. There is valuable knowledge in bringing together the reviewers' [including generg, buzzforb, lhquam etc] input to attempt to connect the subjective with objective performance.
 
I have connected an 8 ohm resistive load to the amp and takes the signal throught a 100K pot to my laptop,I am running audio tester the spectrumanayzator and running an 1khz signal through the amp wich I se on the audiotester but I get no watsoever reaction when turning the pots on the ampmodule.
Is this normal? :confused:
 
Untitled-1_zps0d399b37.jpg


But I don´t know why theres both a blue and red curve when I only have one channel from tha amp connected?Can I turn it off somewhere?
 

6L6

Moderator
Joined 2010
Paid Member
If it's biased, then something else is wrong... your odd-order harmonics are stronger than the even-order, and they are all huge. The only harmonic spikes you should see are 2 and 3.

You are giving the amp a clean 1000Hz sinewave? Don't use squarewaves.

Perhaps it's just a measurement error... does it sound good?
 
Member
Joined 2009
Paid Member
Put your DMM n AC, change for a moment from 1kHz to 200Hz and measure the voltage over the 8R at the output.
Disconnect for security connection to Laptop input......

Do have the 2.83V at 8R for 1Watt or more..?.or less....

Maybe you have to increase or decrease the the input voltage ....

If you have the 2.83V go back to 1kHz and measure again, when the DMM AC shows nearly the same value..... good, if not keep the reduced value in mind and use it in future for the
measurements with 1kHz.
I measure always first the 2.83V and the I look if my pot reduces the value to let us say secure 100-200mV for the laptop...
 
Last edited:
Untitled-1_zps8b923810.jpg


Here is one that I got when turning one off and checking the levels.
But I guess its that first one harmonics thats to large?

Yes its connected to speaker ground.

If I'm not mistaken it should instead look like this:

Only some 2nd and 3rd harmonics visible and the rest down below the noise floor.
 

Attachments

  • Untitled-1_zps8b923810.jpg
    Untitled-1_zps8b923810.jpg
    83.6 KB · Views: 311